void main() {
    int age = 15;
    IO.println(13 <= age <= 19);
}

// From Groundwork, chapter 3 (ch03-expressions-and-operators), box 14.
// This example is from Groundwork, licensed CC BY-NC-SA 4.0.
// Run with: java ch03_14.java
// This fails on purpose: it does not compile—A range written the way it is on paper, which Java refuses. The error message is the lesson.